SquareFrameLayout.java

package me.wangyuwei.signuptransition;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.FrameLayout;

/**
 * 作者： 巴掌 on 16/8/19 13:10
 * Github: https://github.com/JeasonWong
 */
public class SquareFrameLayout extends FrameLayout {

    public SquareFrameLayout(Context context, AttributeSet attrs,
                             int defStyle) {
        super(context, attrs, defStyle);
    }

    public SquareFrameLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public SquareFrameLayout(Context context) {
        super(context);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        setMeasuredDimension(getDefaultSize(0, widthMeasureSpec),
                getDefaultSize(0, heightMeasureSpec));

        int childWidthSize = getMeasuredWidth();
        // 高度和宽度一样
        heightMeasureSpec = widthMeasureSpec = MeasureSpec.makeMeasureSpec(
                childWidthSize, MeasureSpec.EXACTLY);
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

}